Keyrings Archive on lore.kernel.org
 help / color / Atom feed
From: Ard Biesheuvel <ardb@kernel.org>
To: "Stephan Müller" <smueller@chronox.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>,
	Eric Biggers <ebiggers@kernel.org>,
	Jarkko Sakkinen <jarkko@kernel.org>,
	Mat Martineau <mathew.j.martineau@linux.intel.com>,
	David Howells <dhowells@redhat.com>,
	Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
	linux-fscrypt@vger.kernel.org,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	keyrings@vger.kernel.org, simo@redhat.com
Subject: Re: [PATCH v2 0/7] Add KDF implementations to crypto API
Date: Sun, 24 Jan 2021 15:23:29 +0100
Message-ID: <CAMj1kXE=46vk15Ovs8qS96JZRi2xDHHe=QqC=WKbZ-+gx4DL4Q@mail.gmail.com> (raw)
In-Reply-To: <1772794.tdWV9SEqCh@positron.chronox.de>

On Sun, 24 Jan 2021 at 15:10, Stephan Müller <smueller@chronox.de> wrote:
>
> Hi,
>
> The key derviation functions are considered to be a cryptographic
> operation. As cryptographic operations are provided via the kernel
> crypto API, this patch set consolidates the KDF implementations into the
> crypto API.
>
> The KDF implementations are provided as service functions. Yet, the
> interface to the two provided KDFs are identical with the goal to allow
> them to be transformed into a crypto API template eventually.
>

Why? There are typically two reasons to use the crypto API abstractions:
- the algorithm is not known at compile time, so we need the runtime
dispatch that the crypto API implements,
- the algorithm may be implemented by a h/w accelerator which is
discovered at runtime via the driver stack

In other cases, a library API is much more suitable, even in the case
where we may provide arch-specific accelerated implementations of such
an algorithm.



> The KDFs execute a power-on self test with test vectors from commonly
> known sources.
>
> Tbe SP800-108 KDF implementation is used to replace the implementation
> in the keys subsystem. The implementation was verified using the
> keyutils command line test code provided in
> tests/keyctl/dh_compute/valid. All tests show that the expected values
> are calculated with the new code.
>
> The HKDF addition is used to replace the implementation in the filesystem
> crypto extension. This code was tested by using an EXT4 encrypted file
> system that was created and contains files written to by the current
> implementation. Using the new implementation a successful read of the
> existing files was possible and new files / directories were created
> and read successfully. These newly added file system objects could be
> successfully read using the current code. Yet if there is a test suite
> to validate whether the invokcation of the HKDF calculates the same
> result as the existing implementation, I would be happy to validate
> the implementation accordingly.
>
> Changes v2:
>
> * change HKDF function names
> * change HKDF/SP800-108 KDF extract / seed function prototype
> * ensure clearing of memory of destination buffer in KDF implementation
>   if KDF operation fails
> * security DH: split the removal of dead code into separate patch
>
> Stephan Mueller (7):
>   crypto: Add key derivation self-test support code
>   crypto: add SP800-108 counter key derivation function
>   crypto: add RFC5869 HKDF
>   security: DH - remove dead code for zero padding
>   security: DH - use KDF implementation from crypto API
>   fs: use HKDF implementation from kernel crypto API
>   fs: HKDF - remove duplicate memory clearing
>
>  crypto/Kconfig                         |  14 ++
>  crypto/Makefile                        |   6 +
>  crypto/hkdf.c                          | 199 +++++++++++++++++++++++++
>  crypto/kdf_sp800108.c                  | 149 ++++++++++++++++++
>  fs/crypto/Kconfig                      |   2 +-
>  fs/crypto/hkdf.c                       | 103 +++----------
>  include/crypto/hkdf.h                  |  48 ++++++
>  include/crypto/internal/kdf_selftest.h |  71 +++++++++
>  include/crypto/kdf_sp800108.h          |  61 ++++++++
>  security/keys/Kconfig                  |   2 +-
>  security/keys/dh.c                     | 118 ++-------------
>  11 files changed, 586 insertions(+), 187 deletions(-)
>  create mode 100644 crypto/hkdf.c
>  create mode 100644 crypto/kdf_sp800108.c
>  create mode 100644 include/crypto/hkdf.h
>  create mode 100644 include/crypto/internal/kdf_selftest.h
>  create mode 100644 include/crypto/kdf_sp800108.h
>
> --
> 2.26.2
>
>
>
>

  parent reply index

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-01-24 14:01 Stephan Müller
2021-01-24 14:01 ` [PATCH v2 1/7] crypto: Add key derivation self-test support code Stephan Müller
2021-01-24 14:02 ` [PATCH v2 2/7] crypto: add SP800-108 counter key derivation function Stephan Müller
2021-01-24 14:03 ` [PATCH v2 3/7] crypto: add RFC5869 HKDF Stephan Müller
2021-01-28 20:08   ` Eric Biggers
2021-01-24 14:03 ` [PATCH v2 4/7] security: DH - remove dead code for zero padding Stephan Müller
2021-01-24 14:04 ` [PATCH v2 5/7] security: DH - use KDF implementation from crypto API Stephan Müller
2021-01-24 14:04 ` [PATCH v2 6/7] fs: use HKDF implementation from kernel " Stephan Müller
2021-01-28 20:16   ` Eric Biggers
2021-01-28 20:18   ` Eric Biggers
2021-01-24 14:04 ` [PATCH v2 7/7] fs: HKDF - remove duplicate memory clearing Stephan Müller
2021-01-28 20:21   ` Eric Biggers
2021-01-24 14:23 ` Ard Biesheuvel [this message]
2021-01-24 14:32   ` [PATCH v2 0/7] Add KDF implementations to crypto API Ard Biesheuvel
2021-01-24 14:36     ` Stephan Müller
2021-01-24 14:34   ` Stephan Müller

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='CAMj1kXE=46vk15Ovs8qS96JZRi2xDHHe=QqC=WKbZ-+gx4DL4Q@mail.gmail.com' \
    --to=ardb@kernel.org \
    --cc=dhowells@redhat.com \
    --cc=ebiggers@kernel.org \
    --cc=herbert@gondor.apana.org.au \
    --cc=jarkko@kernel.org \
    --cc=keyrings@vger.kernel.org \
    --cc=linux-crypto@vger.kernel.org \
    --cc=linux-fscrypt@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mathew.j.martineau@linux.intel.com \
    --cc=simo@redhat.com \
    --cc=smueller@chronox.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Keyrings Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/keyrings/0 keyrings/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 keyrings keyrings/ https://lore.kernel.org/keyrings \
		keyrings@vger.kernel.org
	public-inbox-index keyrings

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.keyrings


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git